php runtime_error ai_generated true

警告：mysqli::set_charset()：无法获取 mysqli，位于 /var/www/app/src/Database/MysqliConnection.php 第 22 行

Warning: mysqli::set_charset(): Couldn't fetch mysqli in /var/www/app/src/Database/MysqliConnection.php on line 22

ID: php/mysqli-connection-character-set

其他格式: JSON · Markdown 中文 · English
80%修复率
84%置信度
1证据数
2024-01-08首次发现

版本兼容性

版本状态引入弃用备注
PHP 8.0 active — — —
PHP 8.1 active — — —
PHP 8.2 active — — —
MySQL 8.0 active — — —
MariaDB 10.6 active — — —
MariaDB 11.0 active — — —

根因分析

mysqli::set_charset() 方法在一个未连接或连接失败的对象上调用，通常是由于主机、凭据错误或数据库服务器不可用。

English

The mysqli::set_charset() method is called on a connection object that is not connected or has failed to connect, often due to incorrect host, credentials, or database server unavailability.

generic

官方文档

https://www.php.net/manual/en/mysqli.set-charset.php

解决方案

  1. 在设置字符集之前检查连接状态：`if ($mysqli->connect_errno) { die('连接失败：' . $mysqli->connect_error); } $mysqli->set_charset('utf8mb4');`
  2. 验证连接字符串中的 MySQL 主机、端口、用户名和密码；使用 `mysql -h host -P port -u user -p` 从命令行测试。
  3. 确保 MySQL 服务器正在运行并可访问；检查 my.cnf 中的防火墙规则和 bind-address（例如，为远程连接设置 `bind-address = 0.0.0.0`）。

无效尝试

常见但无效的做法:

  1. 80% 失败

    The extension is loaded; the issue is that the connection object is invalid.

  2. 85% 失败

    The server may be fine; the error is in the application configuration.

  3. 90% 失败

    The error is about connection establishment, not script execution duration.